Insects frequently damage plants and prevent them from being used for desirable and beneficial purposes. The tomato fruitworm, Helicoverpa zea (Boddie), and the beet armyworm, Spodoptera exigua (Hubner), for instance, are two of the most serious insect pests of fresh-market and processing tomatoes. Neonates of both species feed on foliage for several days before migrating to the tomato fruit. Larvae bore into fruit, providing entry for the decay organisms, and each larva can damage several fruit before pupation (Wilcox et. al. 1956, University of California, 1985). In California, about 30 million dollars is lost annually from damage to processing tomatoes by larvae of H. zea and S. exigua (Johnson et al. 1986). Because the damage insects cause plants results in such high losses, there is a need for effective strategies to manage pests.
U.S. Pat. No. 4,943,563 teaches the use of cyclic 2,3,4-triacylhexoses to repel insects from plants. The cyclic hexose esters may be formulated into insect repellant compositions by blending them with inert carriers and then used by depositing the resulting compositions upon a surface to be protected from attack by the insects. The cyclic 2,3,4-triacyl hexoses may be utilized as either individual compounds or in mixtures derived, for example, as the result of selective extraction and purification of the epicuticular exudate from plant parts of the plant species Lycopersicon pennellii, its hybrids and progeny.
In the continuing search for more effective pest control agents, it has now been discovered that certain specific non-cyclic esters are effective in preventing insect damage to plants, such as tomatoes and plants of the Lycopersicon pennellii species.
The non-cyclic esters are known compounds having been used previously for high speed engine lubricants and synthetic fibers.